Gliss is a music app which lets you play sound files and mix them easily by drawing on your iPhone. You can get it from Apple's iTunes store.
Launch gliss and experience an hybrid of a sequencer, a game, an instrument and a generative music system. Put sound under your fingertips with 5 different colors to draw notes, sequences and sounds.

List of features:

5 colors to draw different sounds / samples / voices

sample upload via wifi

sample playback in different pitches using various scales

physical tilt-controlled playhead which adapts movements of the hand

physical randomization option: control random pitches with the phone's tilt

muting voices

glissandi over several octaves

free or grid enabled placement of notes

drifting selections

saving / opening of projects

Sample Sets: A new instrument, which takes a list of samples and puts them on the y axis. So instead of controlling the frequency, multiple samples can be played by one colour. This can be used to create beats and rhythms, because you can have one drum set on one colour. Currently samples are played back in full length, although they are represented only by one dot.

Back to original sequence. With a double tap on the randomization button, you can restore the original sequence. In a similar way you can get back to a default tempo, which can be set in the preferences, by double tapping the tempo button.

Recording. You can now record your performance. Double tap on the playback mode button to start recording.

Sequence organisation. Tap on the sequence number and you get a table with all sequences of the project. Here you can also change the position of a sequence, duplicate or delete it.

Change direction but keep tempo. When you lock the tempo, you can now still change the direction.